Electrical plug



H. v. STRYK'ER ELECTRICAL PLUG Filed oct. 13, 1932 lsv/6;, ATTORNEY www@INVENTOR Patented July 11, 1933Y PATENT OFFICE HAROLD V. STRYKER, OFBROOKLYN, NEW YORK ELE GTRICAL PLUG- Application led October 13, 1932.Serial No. 637,570.

The main object of this invention is the provision of an improved plugfor flexible electric cords such as are used to connect electricalappliances to socket outlets in walls and the like, the aim of theinvention being to equip such a plug with a switching mechanism so thatthe current flowing through the cord may be switched on or o at thesource of Vsupply at the outlet.

Anoher object of the invention is the provision of an electric plug suchas above-mentioned with a handle or knob readily acces- A sible on theface of the plug for actuating the switch contained in the plug.

Still another object of the invention is the provision of a novelstructure Jfor such .a switch so that the operability of the switch atall times is assured, and so that the opening and closing of the circuitby the switch o are at all times positive.

Figure 3 is a top plan view of the same.

Figure 4 is a cross-sectional view taken on the line 4.-4 of Figure 1.

Figure 5 is an enlarged perspective view of the contact making andbreaking element of the switch.

Fi view of the plug showing the switch in closed position.

Figure 7 is a bottom plan view of a slightly modified form of the plug.

Referring in detail to the drawing, the numeral 10 represents the bodyof the plug, which is surrounded by an integral peripheral wall 11. Theusual central opening through the wall of the plug is indicated at 12,and through this opening a exible gure 6 is a fragmentary bottom planconductor 13 passes containing the two wires 14. On one side of the wall10, a substantially disc-like metallic base 15 is mounted by having itsears 16, extending from the base, imbedded in holes 17 in the wall 10.An arm 18 extends from one side of the base 15 and is integral with thelatter. The usual terminal screw 19 is provided for locking the end ofthe wire 14 against the base 15. At a short distance from the base 15, asubstantially elongated arm 20 is mounted in the wall 10 by means ofprojecting ears 21 which are imbedded in the material forming the wall.At one end of the arm 20, a disc-like base 22 similar to the base `15 isprovided, and a locking screw 23 is threadably engaged with the base 22.A socket prong 24 extends integrally from, and at right angles to, thearm 20. Diametrically opposite the arm 20, a second arm 25 is mounted inthe wall 10 by means of prongs 26 imbedded in the material of the wall.from the arm 25 and is curved slightly to bring its end in alignmentwith the end of the arm 18.

Adjacent the spaced-apart ends of the arms 18 and 28 the switchingmechanism is mounted. This comprises a metallic ring 31 havingoppositely-disposed ears 29 from which prongs 30 extend at right angles;the latter are imbedded in the composition forming the RisingsubstantiallyI material of the plug. midway between the ears 29 and atright angles to the plane of the ring 31, is a flexible tongue 32 whosethickness is least at its( base and increases progressively toward itstip. Just above its base this tongue is nare ,rowest in width asindicated at 33, and above the point 33 the tongue 32 increases in Widthas well as thickness. It is therefore apparent that if pressure isapplied against the upper end of the tongue while the ring is mountedstationary, the tongue willtend to bend at approximately the point 33.The increased thickness of the upper part of the tongue is indicated bythe numeral 34. The upper end of the tongue is bent into a wave-likecrosssection, thus causing a central boss 35 to appear on one side ofthe tongue, and on the opposite side of the tongue on either side Acontact arm 28 extends of the boss 35, outwardly extending arcuate lips36 and 37 are thereby formed. A pin or shaft 38 is rotatably mounted inthe wall l0 and extends through the central opening of the ring 31. Atone end of this shaft 38, a cam 39 is rigidly mounted, andthe-resiliency of the tongue 32 normally urges the boss 35 at the upperend of the tongue against this cam. On the face of the plug a knurledknob or handle 40 is mounted, and in the latter the free end of theshaft is imbedded.

It is obvious that, assuming the connections shown in Figure 1 to bemade and the plug mounted in a current outlet socket, no current willflow while the` switch is in the open position shown in Figure l. If,however, the shaft 40 is rotated 180, the cam 39 will, near the end ofits rotation, strike against the boss 35 and thus push the upper end ofthe tongue 32 against the ends of the arms 18 and 28 until the lips 36and 37 lie in contact with these ends as shown in Figure 6. Thus the gapbetween the arms 18 and 28 is bridged and current will flow from socketprong 27, through arm 25 and 28, tongue 32, arm 18, base 15, one wire14, into the electrical appliance, back through the other wire 14, base23, arm 20, and prong 24.

In Figure 7 is shown a modification in which the tongue 32 carries thecurrent directly from the terminal base 42 to the prong arm 43 withoutclosing any gap in the arm itself. It is to be'noted that in thismodification the ring 31 is omitted, but instead the shaft 38 isrotatably mounted in an extension 41 of the base 42. When, in this form,the switch is rotated 180 from the position shown in Figure 7, the cam39 will cause the tongue 32 to be thrown against the arm 43, therebyclosing the circuit.

Obviously, modifications in form and structure ma be made Withoutdeparting from the spirit and scope of the invention.

I claim:

1. An electric plug havingv terminal posts adapted to receive the endsof an electrical cord, prongs extending from said plug adapted to beinserted into an electrical socket, one of said prongs lbeingelectrically'connected to one of said terminal posts, the other of saidprongs bein electrically insulated from the other of sai terminal posts,and a.'

switch adapted to electrically connect or disconnect said last-namedprong and said last-named terminal post, said switch comprising a pairof spaced-apart arms mounted. in said plug in electrical series withsaid lastnamed prong and post a shaft rotatably mounted in said plug andhaving a cam rigid thereon, a resilient tongue mounted at one end insaid plug and having itsfree end lying between said cam and the spacebetween said arms, the width of said free end of said tongue beinggreater than thel space between said arms, said free end of said tonguehaving its central portion pressed out to form a boss and a lip on eachside of said boss, said boss being normally urged by said tongue againstsaid cam, said shaft upon rotation causing said cam to push said bossaway from said shaft and said lips into contact with said arms to closethe gap between said arms. f

2. In an electrical plug having a terminal adapted to receive the end ofa wire, a prong protruding from said plug and adapted to be insertedinto an electrical socket, an arm extending integrally from saidterminal, a

second7 arm extending integrally from said prong, the free ends of saidarms being mutually spaced-apart and lying adjacent each other a shaftrotatably mounted in said plug, a cam rigid with said shaft, a resilienttongue mountedat one end said plug. and having its free end lyingbetween said cam and said adjacent ends of said arms, the width of thefree end of said tongue being greater than the distance between saidarms, said free end of said tongue being curved to form a pair ofspaced-apart arcuate lips thereon on one side and a pressed-out boss onthe other side, said shaft upon rotation causing said cam to push s-said boss and tongue toward said arms to protruding from said plugadapted to be inserted into an electrical socket, an arm extending'integrally from said terminal, a second arm extending integrally fromsaid prong, the free ends of said arms being mutually spaced-apart andlying adjacent each l other, a resilient tongue mounted at one end insaidplug and having its other end lying adjacent the ends of said arms,the width of the free end of said tongue being eater than the -distancebetween'said arms, t e thickness of said tongue increasing progressivelyfrom the base toward the free end thereof, the upper end of said tonguelying adjacent said arms and being curved to form a pair ofparcuate lipson opposite sides thereof,-the central portion of the upper end of saidtongue being pressed outward to form a boss a shaft rotatably mounted insaid plug and having a cam rigid with one end-thereof, said lboss beingnormally urged by said tongue against said cam, said cam upon rotationof said shaft pushing said boss away from said shaft and causin said endof said tongue to be pushed towar said ends of said arms until said lipscontact with said' arms and close the gap between said arms.

4. An electrical plug having a terminal adapted to receive the end of awire, a prong protruding from said plug adapted to be inserted into anelectrical socket, an arm extending integrally from said terminal, asecond arm extending integrally from said prong, the free ends of saidarmsbeing mutually spaced-apart and lying adjacent each other, aresilient tongue mounted at one end `in said plug and having its otherend lyling nrigid with one end thereof, said boss being normally urgedby said tongue against said cam, sald cam upon rotation of said shaft.pushing said boss away from said shaft and causing said end of saidtongue to be pushed' toward said ends'of said arms until said lipscontact with said arms and close the gap between said arms.

5. An electrical plug having a terminal adapted to receive the end of awire, a rong protruding from said plug adapted to e inserted into anelectrical socket, an arm extending integrall from said terminal, asecond arm exten ing integrally from said prong, the free ends of saidarms being mutually spaced-apart and lying adjacent each other, aresilient tongue mounted at one end in said plug and having its otherend lying adjacent the ends of said arms, the width of the free end ofsaid tongue being greater than the distance between said arms, the upperend of said tongue lying adjacent said arms and being curved to form apair of arcuate lips on opposite sides thereof, a shaft rotatablymounted in said plug and having a cam rigid with one end thereof, saidtongue being normally urged against said cam, said cam upon rotationpushing said tongue toward'said ends of said arms until said lipscontact with said arms and close the gap between said arms.

In testimony whereof I afx my signature.

HAROLD V. STRYKER.

